Had to move hard disks from one server to another. System boots fine and I can access the command line of the server from the console. However the networking seems broken. the /etc/network/interface file still has the same static IP setup as before. The link light is on on the NIC but I just cannot get it to ping out and am unable to ping the server. pinging the loopback works fine so networking is running.

Using lshw -class network I can see the device I have connected listed.

Am I missing something obvious here or am I going to have to reinstall (which does need to be done at some stage due to some other mistakes I have made oops)